Barclays Center CEO Brett Yormark assured everyone several months ago that the still-under-construction Downtown arena would be fully capable of housing an NHL team in addition to the soon-to-be-Brooklyn Nets of the NBA when it opens later this year.

The prolific publicity man proved true to his word Tuesday morning, when he officially announced that the New York Islanders would host the New Jersey Devils at Barclays for a preseason game on Oct. 2.

That’s more than one full month before the Nets play their home opener in our fair borough.

“We feel Brooklyn is an untapped hockey market that offers the Islanders an exciting opportunity to grow its fan base,” Yormark said in a statement.

“Barclays Center will also afford current Islander fans with great accessibility, as the Long Island Rail Road and nine subway lines will come directly to the arena at the Atlantic Terminal transit hub.”

The Islanders, desperate to find a viable option to their current lease agreement at the Nassau Coliseum, which expires in 2015, have long been rumored as a potential co-tenant to the Nets.

Former Nets owner Bruce Ratner felt Barclays would be a perfect new home for the Islanders, who saw their dreams of a state-of-the-art Nassau County arena dashed by the voting down of a referendum for the much-publicized but ultimately ill-fated Lighthouse Project last summer.

“I think it is highly likely there won’t be a new arena built in Nassau County with the current state of the economy,” Ratner noted in September. “So I think there is certainly a chance (for Brooklyn to get the Islanders).”

Yormark was quick to point out that the facilities at Barclays were built with luring an NHL franchise in mind.

“The Barclays Center will have an ice rink that can support professional hockey,” he said. “Due to the venue’s design, the capacity for hockey would be several thousand seats less than for basketball. While we hope to explore hockey opportunities in the future, our primary focus is to build the best sports and entertainment venue in the world.”

The building, which will have its official opening with a series of Jay-Z concerts in late September, will only hold about 14,500 fans for hockey, which would be the lowest capacity in the NHL.

But that didn’t seem to quell the Islanders’ enthusiasm for playing the Devils just across the Brooklyn Bridge from their bitter rivals, the Rangers, at Madison Square Garden.

“We’re extremely excited to play the first NHL game in the new, state-of-the-art Barclays Center,” Islanders general manager Garth Snow said. “We already have some of the most passionate fans in the league supporting our young team, and we are looking forward to expanding our base into Brooklyn.”

Islanders owner Charles Wang, who has been frustrated by his inability to secure a new arena deal and even threatened to move the team out of the tri-state area all together when the Coliseum lease expires, is a graduate of nearby Brooklyn Tech High School.

The Nets’ long-anticipated opener is scheduled for early November.

The on-sale date for tickets to the Islanders-Devils game will be announced soon, according to Yormark. Fans are encouraged to visit www.barclayscenter.com for more information.